So "uniformed cop" tells you to put a soldier up in your house, you have to do it?
So "uniformed cop" tells you to empty your pockets and stand clear while they ransack your house?
So not everyone in uniform is a police officer.
Surely you are mistaken. As but one example, if a cop shows up at your house and says you need to let him in to search, you can tell him to stuff it.
That's an important distinction. If you're ordered to shoot yourself in the head by a cop, "no" is a perfectly reasonable answer, and likely to stand up in court.
In the "refuse to move on after police asked you to" scenario here, the NYC case "People v. Galpern" is often used as precedent. In that case the defendant was found guilty simply because he was, in the officer's view, obstructing the sidewalk. He was not otherwise disturbing the peace. From this case, the courts tend to side on the judgement of the arresting officer unless there are extreme circumstances.
For those who are interested in reading beyond Galpern, some other relevant classic cases are Terry v. Ohio and People v. Cohen.